Method of flanging bimetallic plate



lAug. 28, 1945. G c. BEISHLINE ETAL 2,383,584.

Filled Jan. 21, 1941 A INVENTORS TTORNE.' v

Patented Aug. 28, 1945 Guy C. Beishline, Berwick, Pa., f and Charles F.y

' Walp, Bualo,'N. Y., assignors to American Car and Foundry Company, NewYork, N. Y., a corporation of New Jersey Application January 21, 1941,serial No. 375,282

' 5 claims. (C1. 29-148) y This invention relates to the anging of platein general and in particular to the langing of bimetallic plate such asused in armoring of mobile or stationary structures.

In the past flanges have been placed around openings in armor or otherplates to provide de-l ectors preventing splash from bullets enteringthe 'gun ports or observation holes. In cases of heavy armor th'eseflanges have been cast in place. In recent years where mobilestructureswere armored the use of cast metal became impossible due to weight andit was necessary to re sort to high strength alloy steels properlytreated to give maximum resistance against penetration. With such highalloy steels properlyY treated a proper ange could not be obtained andthe flange was provided by means of welding a bead around theopeningsand grinding this bead to proper contour but such operation on the platedamaged the plate structure and gavean extremely weak `condition at avery vital point in the armor. It is flange or in backing up the flange,thus producingl an opening surrounded by plate having av maximumstrength up to the very edge of the opening. One of the objects,accordingly, of the invention 'is the production ofthe flangedbimetallic plate having uniform structure in the plate and ange.

`A further object of the invention is th`e production of a bimetauicplate having openings Surjrounded by flanges projecting from the hardside of the plate and with a substantially uniform depth of hardness inthe plate and flange.

' A still further object of the invention is the pro.. duction of abimetallic plate having openings therein surrounded by flangesprojecting from the hardened side of the plate and formed by acompression of the hard surface and backing metal.

These and other objects of the invention will i be apparent to vpersonsskilled in the'art from a study of the following description andaccompanying drawing in which:

Figure l is a sectional Yview through a machiner adapted to operate onthe bimetallic plate which is shown in position on the machine bed; l,

Fig.A 2 is an enlarged sectional view showing the positionof tool partsafter th'e opening has been punched through the bimetallic plate;

Fig. 3 is an enlarged sectional view showing the position of bimetallicplate and' swaging dies at the beginning of the swaging or compressingoperation;

' Fig. 4 is an enlarged sectional View similar to Fig, 3 but showing thetool parts and plate condition upon the completion of the swaging or,compressing operation;

Fig. 5 is a sectional view through the opening in the completed plate; y

Fig. 6 is a front View of the anged opening in the bimetallic plate, and

Fig. '7 is an enlarged sectional'view taken subu stantially on line l-lof Fig. 5 and better disclosing the condition of the metal at theopening.

The high strength alloy steel plates may bereceived from the rollingmills in nal condition to be worked but in most instancesfwill bereceived in a plain rolled condition and must be carburized to producethe hard skin on one surface backed up by softer metal, all of which isso necessary to production of a proper plate capable of resistingpenetration by modern arms. The plates may be carburized in any wellknown manner and after carburizing they must be annealed to produce theproper structure and to soften the plates suliiciently for drilling,punching or other operations. After the plates are annealed they areheated locally and brought to a punching machine such as shown in Fig. 1with the locally heated area in position beneath' the male punchdie. Theplate will be in the condition indicated by th'e drawing, namely, with ahard surface 2 backed up by a relatively softer metal 4 and it should benoted that when in position for punching the hard surface is uppermostand is the first to be contacted by the male die. e

Th'e machine may be of 4any form but in the instance shown comprises aheavy base 6 supporting the bed 8 to which is clamped a heavy stripperplate I0. The female die I2 having the desired opening therein issupported in any suitable mannerupon the bed plate of the machine, whilework positioning guides I4 are clamped or held on the bed in properposition so that the' plate to be punched may be readily brought to itscorrect position between the dies. The female dieY l2 is formed, asclearly shown in Fig. 2, with a considerable taper in orderto permitpassagerof the punched slug, while the throat I6 has considerableclearance C between it and the male die in" order'that the punched platewill have an/opening with tapering sides converging-toward the hard sideof th'e plate, as clearly shown in Fig. 2. The clearanceC between thethroat of the female of any desired contour on its punched face, but inthe instance shown has beentaperedfasatfZZ in order to act moreas ashear and reduce the power necessary to punch ,the"-liigh strengthbimetallic plate. Y

After the bimetalllc platehas been punched'as shown in Fig. 2 it may beimmediately removed to the swaging machinezcprvidedt.enoughih'eat stillremains in the plate, otherwise it.must be reheated locally at theopening, after'which it is :.takenzto `theY swaging machine;l :Theyswaging af: machine: may be '.identicalfzwith the punchingif..machinedescribedtwith the exception: that different tools arecarried by the bed andfram.; 'The tools `carriedbyf.fthefswagingimachine;\ asfshown l'inFigs; 3: and 4,'arearfeinalendiev So'having a -f 1straight.'walled'.fopeningttherethrongh;-.with;.the

upper edge surrounded by at cavityf. of :thecontourldesired rfor 1 thefinal -tange .ron the plate.

The male swaging tool 34-ltlikewiseihasfstraight 'P sides throughout-themajor portion of itsflength,

while the nose is tapereasrat=-35ftdcausezan'upsetting and 'compressionYof:` metal inzsthe bi- '-me'tallic plate. 'The preperly'f:heatedi',bimetallic plate will `be placed oni. the'V -`females"swagingndie`with the hard side downward; .therebyi causing the male swaging tooltor first'. contact f thee' relatively s'oftf'metalforrning'the.tapered. sides. of athe' openning, as' clearly -fshown in .Fig; 3:.which'z. indicates thecontact of'thevmale swaging toolwithfthebimetallic plate'andf after afslight-fdistorting pressure `has fbeen`appliechafiApplication ofwfurther pressure Willf cause the male'swagingwtooltotfmove downwardly rcompressinguthe hard part 2f. ofrthebimetallic-plate and causing it to flow. into the `recess inthe' yfemaledie,whi1e`iat thesamef timeirthe A relativelyvv s'ofter-'metal-is`compressediandfzmade more dense Hadjacentvthe; openingrandthezplateand'- tool then assumdthe position'fandzcondition shown inFig. 4.2 i'Upwardlmovement fof .thermale r die Twill, offcourselift`=thef1biinetallic platesfcom 4x"from the -tool-by means offftheiheavier: :stripper plateVv I0 andmay then beremovedwfronntheimavchineand-thebead orfiange'd'opening .willxappear 1^ as shown nFigs. 5, 6 and7. *:AftertheIplate--has been removed from the swaging machin'euandrprofc vided no'further operations are-tor be performed on the'plate, it maybegivenitsfiinalsheatwtreat placing' it in condition-fjfor-f---application.toe the armored structure. TAS clearly shown intFigs. 4,

` 5 rand 7 the'hard surface of the'iplate-y isfofsubstantially uniformdepth up tothewveryledge of the' openingv land will retain "its..flullis'trengthasince onlycompressive forces have beenfapplied: during 6its distortion, such compressive forcessbeingcapplied not only by theswaging-too1',1but.-by the movement' of hard surface due to' the'fshapeofi/:thecswaging tool'and the taper inthelpuncliediopenngl It isi;

of course,necessary that'fthe volume'of.metal re- `-mainingf in nthe"openingdue'to the vtapered the softer metal forced# toward thepunchinglbe.;properlyf.:proportioned sofasto as fnearly as.lpossiblevexa'ctly supply .the metalinecesvsari' f' in the4compression-1'ora swa'gingc` cperatlon;

Once this volume has been carefully calculated the flanges will appearas shown in Figs. 4, 5 and '7 Which follow almost exactly the etchedsamples taken from actual flanged plates.

Although the invention has been shown and described in considerabledetail, it will be obvious that slight modifications in procedure aswell as considerable `variation in the machinery used will suggestthemselves to persons skilled in the art 1,0 but all such modificationsand procedure and variation in machinery are contemplated aS will"-Lfallwithin thescope of the following claims dening our invention.

What isclaimed is:

v 1:,The method of providing a hard surfaced inetegral flange .on abimetallic plate having a hard surface backed up by a relatively softermetal,

which consists in punching an opening in the c plate by moving a slug ofmetal from the hard surface through the softer backing metal, and

:hthen' formingthe vangebyaforcingfaf'swaging tool f .z through the:opening .-towardrfthe :hardxsurface: sifrmultaneouslycompressingithesofter:rnetal-;foi'rn ing the sides of theopeningl andmovmg lthetsame itowardthe hard surface to bend: .theeflatter outf award1y` and form-theflange.

i 2.- Thamethod of providing aihardxsurfacediinfr te-gral .flange ona'bimetallic plate ahaving afhard sur-facerbacked'iupwby a relatively.:softer-l metal, which' consistsin forcingl annundersizepunchifrom thehard-surfacethrough the softerimetal t'oform `an opening'w'ithsidesfhaving a predetermined -\taper;fand' then'y sizing theIepenlngA/.andxforming 'j thehardssurfaced flange by forcing a1swagingtool 3D through-the open-ingitoward'y the hardi-surface sif-multaneously compressing fthe: softermetallformingA the tapering sidesof theropen-ingandim'oving the same toward thehardfsurface to bend-thelat- -'-ter outwardly forming theflange.

` 3'.' The rmethodof providing 'afbimeta-llicfintegral flange-on abimetallictplate each having a hard outer surface backed` up bya`lrelatively 'softer metal, 'which consists irr-formingan'openh1"sing inthe plate andthen forming' thevflangev` by "c forcing ay swaging toolAthrough fthe opening "toward thevhard surface -`simultaneouslycompressing the softer metal forming the si'des'- ofvthe 'openingand`moving the'same -toward th'elhard 'surface tobend-the latter outwardlythereby forming the bimetallicflange.

' 4. The method of providing abimetallicinte- "j'gral-*angeon abimet'allic"plateeachhaving a hard'outer surfacebackedup byrelativelys'ofter metal, which consists inpunching in" the 'plate'. an

fr "0opening having sidesv of aipredeterminedtaper converging toward thehard surface and containing'sucient metal to .form theflange, and thenforming the bimetallic flange and' simultaneously straightening thesides of theopeningbyforcing a swagingv tool vthrough thetopening.toward the fhard surface.

. 5. 'Thecmethod of providing ay bimetallic. integral yfiangeonabimetallic .plategeachlhaving a 5 lhard cuter ysurface backedup,by..a:relatively vsofter metalsA `which :consists in 'forming .inrtheeplate an .opening having ltaperingsdes converging 4toward l,-thefhard-surface of .the ,plategf-and then straightening the sides ofthe-opening.andsimultaneously forming. theqbimetallic.- .fflangef` by'`forcing the 'sof-ter metal of .theJtapering.sidestowardthethard surface.ltherebyebending thea-:hard :surface nutwardlyandfforrningthebimetallidflange. GUY C,-.BEISHI;INE. ..:CHARLES `Fc WALP.

